Table of Contents
Advertisement
Downconverter Operation
AM Noise Measurement (IF AM Detector) System Control
•
Input Attenuation: determined by the system if AUTO is selected above.
•
IF Gain: determined by the system if AUTO is selected above.
•
Mixer Maximum Level: system enters factory default value, –5 dBm.
•
Tuning Sensitivity: system enters factory default value.
•
LO Power: system enters factory default value.
•
Auto/Manual LO Frequency Selection: AUTO
•
LO Frequency: determined by the system.
•
100 MHz Ref. Chain PLL Bandwidth: system enters factory default
value.
•
600 MHz Ref. Chain PLL Bandwidth: system enters factory default
value.
•
System Spectrum Analyzer Connection Port: HP 11848A
Step 2 - Begin a new measurement
When the HP 3048A software pauses at the system connect diagram,
connect the DUT to the downconverter's SIGNAL input and make any other
connections shown that haven't been done yet.
Step 3 - Autorange the downconverter
Press the
DC Auto Range
This triggers a one-time autoranging of the downconverter's input attenuator.
Step 4 - Measure the AM detector's output voltage
The detector's output voltage is measured with the downconverter's internal
voltmeter.
1. Read the
AM DET Voltage:
2. Press the HP 3048A
3. Press the HP 3048A
4. Repeat from step 1 above until the reading on the
display doesn't change from one reading to the next.
5. Record the final reading for use in the next step.
Step 5 - Measure and adjust the calibration source power
Connect the calibration source's output to the downconverter's SIGNAL
input.
Set up the calibration source as follows:
•
Frequency: Use the DUT frequency.
3-36 HP 70427A/HP 70428A User's Guide
softkey on the HP 3048A controller.
display.
softkey.
Update AM Det.
softkey again.
Update AM Det.
AM Det Voltage:
Advertisement
Table of Contents
